Side frame-bolster interlocking arrangement for snubbed trucks



N 1963 c. E. TACK SIDE FRAME-BOLSTER INTERLOCKING ARRANGEMENT FORSNUBBED 'mucxs Flled Nov 6, 1959 2 Sheets-Sheet l 1 w v n INVENTOR.v 5Ma @104 Nov. 5, 1963 c. E. TACK SIDE FRAME-BOLSTER INTERLOCKINGARRANGEMENT FOR SNUBBED TRUCKS 2 Sheets-Sheet 2 Filed Nov. 6. 1959United States Patent F 3 109,387 SIDE FRAME-BOLSTER INTERLOCKING AR-RANGEMENT FGR SNUBBED TRUCKS Carl E. Tack, Elmhurst, IiL, assignor toAmsted Industries Incorporated, Chicago, Ill., a corporation of New r eJe s y Filed Nov. 6, 1959, Ser. No. 851,423

3 (Iiaims. (Cl. 105-197) This invention relates to railway freight carsnubbed trucks, and more particularly to an improved side framebolsterinterlocking arrangement therefor.

The invention comprehends a side frame-bolster interlocking arrangementadapted to prevent or minimize horizontal and rotational movement of thebolster relative to the side frames.

Before the present day snubbed trucks came into existence, all of thefreight car trucks were constructed with a minimum of clearance betweenthe inside surfaces of the side frame column walls and the adjacentouter surfaces of the bolster side walls, so that transverse shifting ofthe bolster on the load supporting springs in a direction longitudinalof the truck and also rotation of the bolster about its longitudinalaxis was minimal and not sufficient to create any problems.

In the snubbed trucks of the present day freight cars, however, in orderfor the snubbing mechanisms to be operable the friction shoes must haveroom to move transversely of the bolster as they are actuated by theirsprings. When the friction springs are in normal compressed or expandedcondition they urge their related friction shoes into snug engagementwith the adjacent side frame column surfaces and normally in so doingserve to maintain clearance between the bolster and side frame columns.However, it has been found that in certain instances where cars havebeen subjected to unusually severe longitudinal jolts or bumps, as aresult of abusive humping practices, bolsters have been displaced tosuch an extent that the friction springs are no longer effective inmaintaining proper clearance between the bolster and side frame columnsurfaces.

As most cars can incur bumps at speeds up to six miles per hour withouthaving their bolsters displaced, this problem does not occur duringnormal switching operations but only as a result of negligent orcareless handling of the cars during switching or humping operations.

Although in recent years the introduction of automatic classificationyards has reduced, to a certain extent, the great volume of conventionalswitching operations Wherein freight cars are humped, nevertheless it iscompletely impossible to eliminate humping altogether.

Actual tests have demonstrated that at speeds of approximately mph. orgreater there is a tendency of the bolster to rotate about itslongitudinal axis relative to the side frame. With the arrested motionof the car body the truck tends to continue forward and an instantaneoustilting action is imparted to the truck bolster, releasing part of thesupporting springs, and, if violent enough, enabling the springs to popout of the side frames.

Another result of severe shock is that with the truck tending tocontinue forward the rotational movement of the bolster tends to releasethe forward supporting springs and compress the rear springs, so thatthe bolster is jammed against forward side frame columns and releasedfrom the rear side frame columns. With the bolster tilted and jammedagainst one pair of side frame columns the friction devices on the sideof the bolster adjacent those columns are over-compressed while thefriction devices on the opposite sides of the bolster are over-extended.This naturally produces abnormal wear patterns 3,109,387 Patented Nov.5, 1963 ice If the bolster has been jammed against corresponding sideframe columns with enough force, it can shift laterally on the loadsupporting springs so that the frictional resistance between the uppersurfaces of the load springs and the lower surface of the bolster is toogreater to permit the bolster to return, or be urged by the frictionsprings, to proper position relative to the side frame columns.

It is possible that a relatively slight displacement of the bolster anda minor dislodgement of the load springs could occur without beingnoticed as a car continues in service. Under these conditions snubbingaction would still take place as the load taken from the snubbingdevices on one side of the bolster would be added to the other; however,uneven or erratic wear patterns would occur and the service life of theparts would be shortened.

Thus, inasmuch as a snubbed truck requires a definite predetermineddistance between the side frame columns and the friction shoes in thebolster opening, in order to prevent any erratic or uneven wear patternson the snubbing surfaces and to insure optimum service life of theparts, it is desirable to maintain this distance and provide some othermeans for restricting horizontal or rotative movement of the bolsterWithin the opening.

Accordingly, it is a primary object of this invention to provide in asnubbed railway car truck a means of restricting undesirable horizontalor rotative movement of the bolster relative to the side frames withoutdecreasing the space between the friction surfaces of the side framecolumn walls.

A more specific object of the invention is the provision of a sideframe-bolster arrangement having special stop means on the side frame,engageable with the side walls illustrated in FIGURE 1, with portions ofthe structure shown in vertical section;

FIGURE 3 is an enlarged top plan view of a portion of the structureillustrated in FIGURE 1, with portions of the structure shown inhorizontal section, and

FIGURES 4 and 5 are schematic diagrams illustrating the relationship ofrelated bolster and side frame column surfaces in a conventional snubbedtruck and in a snubbed truck embodying features of the invention,respectively.

It will be understood that certain elements have been intentionallyomitted from certain views where they are illustrated to betteradvantage in other views.

Referring now to the drawings for a better understanding of theinvention it will be seen that the invention is applied to a railway cartruck comprising a pair of side frames, indicated generally at 10, whichare interconnected by a transversely extending bolster, indicatedgenerally at 12, and which are supported at their ends by a pair ofwheel and axle assemblies, indicated generally at 14. Only portions ofone side frame and one Wheel and axle assembly are shown in the drawingsas the side frames are identical, as are the wheel and axle assemblies,and each side frame is symmetrical with respect to its verticaltransverse center plane.

As best seen in FIGURE 1, each side frame comprises 3 a pair oflongitudinally extending tension and compression elements 16 and 18,respectively, which are merged at their ends to form housing means 20for journally receiving the wheel and axle assemblies 14 in aconventional manner. Intermediate of their ends the tension andcompression elements are spaced from each other and interconnected by apair of integral vertically extending columns Z2 spaced from each otherlengthwise of the side frame to define a holster opening 24therebetween.

As best seen in FIGURE 1, bolster 12 includes a pair of box-like ends 26(only one of which is shown) each of which is supported on a pluralityof coil compression load springs 28 which in turn are positioned on aspring seat 60 presented by side frame tension element 16 in bolsteropening 24.

Each bolster end, as best seen in FIGURE II, has a pair of pockets 3-2disposed on opposite sides thereof adjacent related side frame columns22. Within each pocket there is provided a friction shoe 34 and spring36 operable to urge the shoe into frictional engagement with a Wedgewall 38 presented in the bolster pocket and with a vertical frictionsurface 4% presented by a wear plate 4I2 rigidly secured to a verticalwall 44 of the adjacent side frame column 22.

The structure of the friction shoe and spring arrangement is notshown indetail as it does not form an essential part of this invention and maybe of any desired type such as that described and illustrated in detailin Patent 2,378,414, particularly in connection with FIGURES It is wellknown by those familiar with the art of railway car trucks that snubbingdevices of the type previously described are commonly used to dampvertical oscillations of the bolster supporting springs 28. In theiroperation the friction springs 36 react between the bolster and frictionshoes to urge the shoes up against the wedge walls 38 and the wedgingaction between the wedge walls and the shoes urges the shoes outwardlyand into frictional engagement with friction surfaces presented byadjacent side frame columns. The entire snubbing arrangement can bereversed with the friction shoes and springs being carried in pockets ofthe side frame oolumns so that the friction springs react between theside frame columns and the shoes to urge the shoes into engagement withwedge walls in the columns and with vertical side walls of the bolster.In either arrangement the result is the same. In both arrangements (onlythe first described arrangementbeing herein illustrated) the bolsteropening must be wide enough to afford some degree of lateral orsidewisemovement in the bolster opening in a direction lengthwise of theside frame. It is also known that the bolster must be afforded freedomfor some limited degree of lengthwise movement in a direction sidewiseof the side frame.

Longitudinal movement of the bolster can be limited by providing on eachside of the bolster end a pair of inboard and outboard lugs tor gibs 4.6and 48, respectively,

which project in a direction normal to the longitudinal axis of the,bolster and which are disposed adjacent the inboard and outboard sides,respectively, of inboard and outboard vertical flanges 50 and 52,respectively, of the side frame columns.

Although the friction shoes are only aiforded a limited degree ofhorizontal movement, they can not be used as stop means to limitsidewise movement of the bolster between the columns of the side frame,because if they were the only stop means they would merely ride back andforth on the wedge walls and permit the bolster to move freely in bothvertical and horizontal directions.

In the prior art the means for limiting lateral or sidewise movement ofthe bolster between the side frame columns has been the engagementbetween the corners 56 or the sideframe columns, which are locatedoutboardly adjacent opposite sides of the wear plates 4-2, and theadjaopening of the side frame.

cent shoulders 54 of the bolster, which are located inboardly adjacentopposite sides of the bolster pockets 32.

In the prior art devices there has been a great variation in the amountof over all distance provided between the side frame column flangesurfaces 56 and the bolster wall vertical surfaces 54, but in all casesthis distance was so great as to permit an undesirable amount of lateralshifting of the bolster in the bolster opening of the side frame. As aresult of this excessive play, when cars are subjected to extremelongitudinal shocks as in coupling operations, the bolster tends to dotwo things: It shifts sideways up against the forwardmost columnscausing the load springs 28 to tilt, or angle relative to the vertical.When this occurs the springs sometimes remain in a tilted or cookedposition and maintain the bolster jammed up against the front columns sothat it never centers itself. This results in a malfunction of thesnubbing means as the car continues in service. Also, at times oflongitudinal shock to the car the bolster, if permitted an excessiveamount of play, tends to rotate about its longitudinal axis. Rotation ofthe bolster member, if great enough, can cause the load springs 2-8 topop right out of the car, or at least tilt enough to jam the bolsteragainst. the front columns. Also, if great enough, it can displace thepivotal connection between the bolster and car body.

Although the harmful effects of bolster rotation or shifting were knownin the art, no way was known to reduce the clearance between the bolsterand side frame members in a manner that would still perrnit easyassembly of the truck and proper functioning of the snubbing means.

Attempts were made to build up the surfaces 54 of the bolster so as todecrease the distance between them and the adjacent surfaces 56 of theside frame, but because the areas of contact between them are so smalland the pressure is so great these corner and shoulder surfaces woredown, after extremely brief periods of service, to the point whereexcess play between the members again occurred.

I have discovered that lateral movement of the bolster can be properlyrestricted to the desired degree by providing stop lugs 58 on theinboard sides of inboard flanges of the side member columns. Stop lugs58 extend in- ,boardly and present surfaces 60 which face outwardlyfacing surfaces 62 presented by adjacent inboard bolster gibs 46. Withthis arrangement, if surfaces 60 are disposed a proper distance fromsurfaces 62, the holster movement can be limited to that degree which isabsolutely necessary.

Although prior art devices, such as that disclosed in the previouslymentioned Patent 2,378,414 have been pro columns, and thereby eliminatethe need for providing bolster gibs on both the inboard and outboardsides of the side frame columns. In these prior art devices the columnlugs were never intended to function as a stop means for limitingsidewise or transverse movement of the bolster lengthwise of the sideframe in the holster This sidewise bolster movement was, in conventionalsnubbed trucks, limited by the engagement between the surfaces 54 of thebolster side walls and the surfaces 56 presented by the side framecolumn flanges 5 0 and 52.

As the clearance between the bolster gibs and side frame column lugs wasgreater than the clearance between the related vertical surfaces of thebolster and side frame columns, the latter clearance was controlling anddetermined the maximum amount of movement of the bolster in the bolsteropening of the side frame.

FIGURES 4 and 5 are schematic diagrams illustrating the relationship ofengaging bolster and side frame column surfaces in conventional snubbedtruck arrangements and in a snubbed truck embodying my invention,respectively.

The dimensions for both figures are based on the nominal dimensions of:a conventional 50 ton snubbed truck and are as follows:

FIGURE 4 (Conventional Snubbed Truck) BDistance between bolster gibsurfaces (62 62) 16 /8 C-Distance between side frame column stopsurfaces 6fl6i3) 16 D'Effective transverse diagonal dimension of bolster17. 12 2E-Overall clearance between bolster and side frame surfacesE'-Clearance at one side between bolster and side frame surfaces In thearrangement illustrated in FIGURE 4 the ratio of the overall clearancebetween the bolster and side frame surfaces (2E) to the effectivetransverse diagonal bolster dimension (D) is approximately 3 to 100 or,in other words, the clearance is 3% of the effective bolster dimension.In this arrangement the bolster is free to 1'0- tate about itslongitudinal axis to the extent that it can angle in excess of 7relative to the horizontal.

In the arrangement of FIGURE 5, however, the ratio of the overallclearance (213') between the bolster and side frame surfaces to theeffective transverse diagonal bolster dimension (D) is approximately 1to 100 or in other words the clearance is 1% of the effective bolsterdimension. In this arrangement the spacing between the abutment surfacesso and 62 is less than one-quarter inch and the maximum angle ofrotation for the bolster is less than 2.

The difference between the amount of rotation permitted in conventionalsnubbed trucks and that permitted in snubbed trucks embodying my novelbolster stop arrangement has been proven by actual tests to be highlysignificant.

When cars equipped with conventional snubbed trucks were subjected tobumping shocks at speeds in excess of 10 m.p.h., bolster displacementwas a common occurrence; whereas cars equipped with trucks having mybolster stop application were subjected to bumping shocks at speeds upto 18 mph. without appreciable bolster displacement.

I claim:

1. In a railway car truck the combination of: a side frame having a pairof spaced rigid vertical columns defining a bolster receiving openingtherebetween; vertically extending frictional guide surfaces formed onrespective columns in planes substantially transverse to said sideframe; a bolster member extending transversely of said side frame andhaving an end extending through said opening; snubbing means carried bysaid bolster and resiliently urged outwardly against said frictionalguide surfaces in a manner causing clearances between the sides of saidbolster and said columns; spring means in said opening supporting saidbolster end on said side frame; first abutment surfaces formed on saidvertical columns inboard of said side frame in planes substantiallylongitudinal of said frame; second abutment surfaces formed on saidvertical columns outboard of said side frame in planes substantiallylongitudinal of said frame; first vertically extending gibs formed onsaid bolster end outboard of said side frame; third abutment surfacesformed on said firs-t gibs in a manner causing said second and thirdabutment surfaces to be in juxtaposition to each other; secondvertically extending gibs formed on said bolster end inboard of saidside frame; fourth abutment surfaces formed on said second gibs in amanner causing said first and fourth abutment surfaces to be injuxtaposition to each other; third vertically extending gibs formed onthe inboard side of said side frame and oppositely disposed about saidbolster; fifth vertically extending abutment surfaces formed on saidthird gibs in planes substantially transverse to said side frame; andvertically extending sixth abutment surfaces formed on said second gibssubstantially transverse to said side frame and in juxtaposition to saidfifth abutment surfaces; said respective fifth abutment surfaces andsaid respective sixth abutment surfaces being so spaced from each otherso as to have a total clearance therebetween no greater than one-quarterinch and substantially less than the total clearance existing betweensaid sides of said bolster and said friction guide surfaces on saidcolumns, whereby rotation of the bolster about its longitudinal axis islimited to less than 2.

2. In a railway car truck the combination of: a side frame having a pairof spaced rigid vertical columns defining a bolster receiving openingtherebetween; vertically extending friction surfaces formed onrespective columns in planes substantially transverse tosaid side frame;a bolster member extending transversely of said side frame and having anend extending through said opening; snubbing means carried by saidbolster and resiliently urged outwardly against at least one of saidfriction surfaces in a manner causing a clearance between said bolsterand said columns; resilient means in said opening supporting saidbolster end on said side frame; first abutment surfaces formed on saidvertical columns inboard of said side frame; second abutment surfacesformed on said vertical columns outboard of said side frame; firstvertically extending gibs formed on said bolster end outboard of saidside frame; third abutment surf-aces formed on said first gibs in amanner causing said second and third abutment surfaces to be injuxtaposition to each other; second vertically extending gibs formed onsaid bolster end inboard of said side frame; fourth abutment surfacesformed on said second gibs in a manner causing said first and fourthabutment surfaces to be in juxtaposition to each other; third verticallyextending gibs formed on the inboard side of said side frame andoppositely disposed about said bolster; fifth vertically extendingabutment surfaces formed on said third gibs in planes substantiallytransverse to said side frame; and vertically extending sixth abutmentsurfaces formed on said second gibs substantially transverse to saidside frame and in juxtaposition to said fifth abutment surfaces; saidrespective fifth abutment surfaces andsaid respective sixth abutmentsurfaces being so spaced from. each other so as to have the totalclearance therebetween no greater than one-quarter inch andsubstantially less than said clearance existing between said bolster andsaid friction surfaces on said columns, whereby rotation of the bolsterabout its longitudinal axis is limited to less than 2.

3. A railway car truck, comprising a side frame having axle journalmeans at its ends, a bolster resiliently mounted on said side frame,first means for positively limiting relative lateral movement of saidbolster transversely of said side frame, second resilient meanseffective for inhibiting both the vertical movement of said bolsterrelative to said side frame and the lateral movement of said bolsterlongitudinally of said side frame, and additional means for positivelylimiting rotation of the bolster about its longitudinal axis to lessthan 2, said additional means comprising rigid abutment means on thebolster and frame for positively limiting the total lateral movement ofsaid bolster longitudinally of said side frame to a distance no greaterthan one-quarter inch and less than that distance permitted by saidsecond resilient means.

UNITED STATES PATENTS Clasen -4 Jan. 6, 1931 Hamilton Apr. 14, 1931Hobson Feb. 20, 1940 Darrows May 14, 1940 Cottrell Apr. 5, 1949 CottrellJan. 24, 1950 Le-ese n Feb. 14, 1950 Settles Nov. 15, 1955

1. IN A RAILWAY CAR TRUCK THE COMBINATION OF: A SIDE FRAME HAVING A PAIROF SPACED RIGID VERTICAL COLUMNS DEFINING A BOLSTER RECEIVING OPENINGTHEREBETWEEN; VERTICALLY EXTENDING FRICTIONAL GUIDE SURFACES FORMED ONRESPECTIVE COLUMNS IN PLANES SUBSTANTIALLY TRANSVERSE TO SAID SIDEFRAME; A BOLSTER MEMBER EXTENDING TRANSVERSELY OF SAID SIDE FRAME ANDHAVING AN END EXTENDING THROUGH SAID OPENING; SNUBBING MEANS CARRIED BYSAID BOLSTER AND RESILIENTLY URGED OUTWARDLY AGAINST SAID FRICTIONALGUIDE SURFACES IN A MANNER CAUSING CLEARANCES BETWEEN THE SIDES OF SAIDBOLSTER AND SAID COLUMNS; SPRING MEANS IN SAID OPENING SUPPORTING SAIDBOLSTER END ON SAID SIDE FRAME; FIRST ABUTMENT SURFACES FORMED ON SAIDVERTICAL COLUMNS INBOARD OF SAID SIDE FRAME IT PLANES SUBSTANTIALLYLONGITUDINAL OF SAID FRAME; SECOND ABUTMENT SURFACES FORMED ON SAIDVERTICAL COLUMNS OUTBOARD OF SAID SIDE FRAME IN PLANES SUBSTANTIALLYLONGITUDINAL OF SAID FRAME; FIRST VERTICALLY EXTENDING GIBS FORMED ONSAID BOLSTER END OUTBOARD OF SAID SIDE FRAME; THIRD ABUTMENT SURFACESFORMED ON SAID FIRST GIBS IN A MANNER CAUSING SAID SECOND AND THIRDABUTMENT SURFACES TO BE IN JUXTAPOSITION TO EACH OTHER; SECONDVERTICALLY EXTENDING GIBS FORMED ON SAID